1. Field of the Invention
This invention relates to a process for preparing allylic sulfones of the general formula (I), ##STR3## wherein R is a hydrogen atom or a lower alkyl group, and containing both cis and trans isomers, or cyclogeranyl sulfone of general formula (II), ##STR4## wherein R is a hydrogen atom or a lower alkyl group, and a double bond exists at either one of the positions of the dotted bonds.
The allylic sulfone of general formula (I) and cyclogeranyl sulfone of general formula (II) are useful as intermediates for preparing vitamin A or vitamin A acetate used as a drug or a feed additive. (See Japanese Patent Publication No. 57-48549, and Otera et al. J. Org. Chem. 51, 3834 (1986)).